src/syssignal.h

   1 /* syssignal.h - System-dependent definitions for signals.
   2    Copyright (C) 1993, 1999, 2001, 2002, 2003, 2004,
   3                  2005, 2006, 2007  Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs; see the file COPYING.  If not, write to
  19 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 extern void init_signals P_ ((void));
  23
  24 #ifdef HAVE_GTK_AND_PTHREAD
  25 #include <pthread.h>
  26 extern pthread_t main_thread;
  27 #endif
  28
  29 #ifdef POSIX_SIGNALS
  30
  31 /* Don't #include <signal.h>.  That header should always be #included
  32    before "config.h", because some configuration files (like s/hpux.h)
  33    indicate that SIGIO doesn't work by #undef-ing SIGIO.  If this file
  34    #includes <signal.h>, then that will re-#define SIGIO and confuse
  35    things.  */
  36
  37 #define SIGMASKTYPE sigset_t
  38
  39 #define SIGEMPTYMASK (empty_mask)
  40 #define SIGFULLMASK (full_mask)
  41 extern sigset_t empty_mask, full_mask;
  42
  43 /* POSIX pretty much destroys any possibility of writing sigmask as a
  44    macro in standard C.  We always define our own version because the
  45    predefined macro in Glibc 2.1 is only provided for compatility for old
  46    programs that use int as signal mask type.  */
  47 #undef sigmask
  48 #ifdef __GNUC__
  49 #define sigmask(SIG)                            \
  50   ({                                            \
  51     sigset_t _mask;                             \
  52     sigemptyset (&_mask);                       \
  53     sigaddset (&_mask, SIG);                    \
  54     _mask;                                      \
  55   })
  56 #else /* ! defined (__GNUC__) */
  57 extern sigset_t sys_sigmask ();
  58 #define sigmask(SIG) (sys_sigmask (SIG))
  59 #endif /* ! defined (__GNUC__) */
  60
  61 #undef sigpause
  62 #define sigpause(MASK)    sigsuspend (&(MASK))
  63
  64 #define sigblock(SIG)    sys_sigblock (SIG)
  65 #define sigunblock(SIG)  sys_sigunblock (SIG)
  66 #ifndef sigsetmask
  67 #define sigsetmask(SIG)  sys_sigsetmask (SIG)
  68 #endif
  69 #define sighold(SIG)     ONLY_USED_IN_BSD_4_1
  70 #define sigrelse(SIG)    ONLY_USED_IN_BSD_4_1
  71 #undef signal
  72 #define signal(SIG,ACT)      sys_signal(SIG,ACT)
  73
  74 /* Whether this is what all systems want or not, this is what
  75    appears to be assumed in the source, for example data.c:arith_error.  */
  76 typedef RETSIGTYPE (*signal_handler_t) (/*int*/);
  77
  78 signal_handler_t sys_signal P_ ((int signal_number, signal_handler_t action));
  79 sigset_t sys_sigblock   P_ ((sigset_t new_mask));
  80 sigset_t sys_sigunblock P_ ((sigset_t new_mask));
  81 sigset_t sys_sigsetmask P_ ((sigset_t new_mask));
  82
  83 #define sys_sigdel(MASK,SIG) sigdelset (&MASK,SIG)
  84
  85 #else /* ! defined (POSIX_SIGNALS) */
  86 #ifdef USG5_4
  87
  88 extern SIGMASKTYPE sigprocmask_set;
  89
  90 #ifndef sigblock
  91 #define sigblock(sig)                                   \
  92      (sigprocmask_set = SIGEMPTYMASK | (sig),           \
  93       sigprocmask (SIG_BLOCK, &sigprocmask_set, NULL))
  94 #endif
  95
  96 #ifndef sigunblock
  97 #define sigunblock(sig)                                         \
  98      (sigprocmask_set = SIGFULLMASK & ~(sig),                   \
  99       sigprocmask (SIG_SETMASK, &sigprocmask_set, NULL))
 100 #endif
 101
 102 #else
 103 #ifdef USG
 104
 105 #ifndef sigunblock
 106 #define sigunblock(sig)
 107 #endif
 108
 109 #else
 110
 111 #ifndef sigunblock
 112 #define sigunblock(SIG) \
 113 { SIGMASKTYPE omask = sigblock (SIGEMPTYMASK); sigsetmask (omask & ~SIG); }
 114 #endif
 115
 116 #endif /* ! defined (USG) */
 117 #endif /* ! defined (USG5_4) */
 118 #endif /* ! defined (POSIX_SIGNALS) */
 119
 120 #ifndef SIGMASKTYPE
 121 #define SIGMASKTYPE int
 122 #endif
 123
 124 #ifndef SIGEMPTYMASK
 125 #define SIGEMPTYMASK (0)
 126 #endif
 127
 128 #ifndef SIGFULLMASK
 129 #define SIGFULLMASK (0xffffffff)
 130 #endif
 131
 132 #ifndef sigmask
 133 #define sigmask(no) (1L << ((no) - 1))
 134 #endif
 135
 136 #ifndef sigunblock
 137 #define sigunblock(SIG) \
 138 { SIGMASKTYPE omask = sigblock (SIGFULLMASK); sigsetmask (omask & ~SIG); }
 139 #endif
 140
 141 #ifndef BSD4_1
 142 #define sigfree() sigsetmask (SIGEMPTYMASK)
 143 #endif /* not BSD4_1 */
 144
 145 #if defined (SIGINFO) && defined (BROKEN_SIGINFO)
 146 #undef SIGINFO
 147 #endif
 148 #if defined (SIGIO) && defined (BROKEN_SIGIO)
 149 # undef SIGIO
 150 # if defined (__Lynx__)
 151 # undef SIGPOLL /* Defined as SIGIO on LynxOS */
 152 # endif
 153 #endif
 154 #if defined (SIGPOLL) && defined (BROKEN_SIGPOLL)
 155 #undef SIGPOLL
 156 #endif
 157 #if defined (SIGTSTP) && defined (BROKEN_SIGTSTP)
 158 #undef SIGTSTP
 159 #endif
 160 #if defined (SIGURG) && defined (BROKEN_SIGURG)
 161 #undef SIGURG
 162 #endif
 163 #if defined (SIGAIO) && defined (BROKEN_SIGAIO)
 164 #undef SIGAIO
 165 #endif
 166 #if defined (SIGPTY) && defined (BROKEN_SIGPTY)
 167 #undef SIGPTY
 168 #endif
 169
 170
 171 #if NSIG < NSIG_MINIMUM
 172 # ifdef NSIG
 173 #  undef NSIG
 174 # endif
 175 # define NSIG NSIG_MINIMUM
 176 #endif
 177
 178 #ifdef BSD4_1
 179 #define SIGIO SIGTINT
 180 /* sigfree is in sysdep.c */
 181 #endif /* BSD4_1 */
 182
 183 /* On bsd, [man says] kill does not accept a negative number to kill a pgrp.
 184    Must do that using the killpg call.  */
 185 #ifdef BSD_SYSTEM
 186 #define EMACS_KILLPG(gid, signo) (killpg ( (gid), (signo)))
 187 #else
 188 #ifdef WINDOWSNT
 189 #define EMACS_KILLPG(gid, signo) (kill (gid, signo))
 190 #else
 191 #define EMACS_KILLPG(gid, signo) (kill   (-(gid), (signo)))
 192 #endif
 193 #endif
 194
 195 /* Define SIGCHLD as an alias for SIGCLD.  There are many conditionals
 196    testing SIGCHLD.  */
 197 #ifndef VMS
 198 #ifdef SIGCLD
 199 #ifndef SIGCHLD
 200 #define SIGCHLD SIGCLD
 201 #endif /* SIGCHLD */
 202 #endif /* ! defined (SIGCLD) */
 203 #endif /* VMS */
 204
 205 #ifndef HAVE_STRSIGNAL
 206 /* strsignal is in sysdep.c */
 207 char *strsignal ();
 208 #endif
 209
 210 #ifdef HAVE_GTK_AND_PTHREAD
 211 #define SIGNAL_THREAD_CHECK(signo)                                      \
 212   do {                                                                  \
 213     if (!pthread_equal (pthread_self (), main_thread))                  \
 214       {                                                                 \
 215         /* POSIX says any thread can receive the signal.  On GNU/Linux  \
 216            that is not true, but for other systems (FreeBSD at least)   \
 217            it is.  So direct the signal to the correct thread and block \
 218            it from this thread.  */                                     \
 219         sigset_t new_mask;                                              \
 220                                                                         \
 221         sigemptyset (&new_mask);                                        \
 222         sigaddset (&new_mask, signo);                                   \
 223         pthread_sigmask (SIG_BLOCK, &new_mask, 0);                      \
 224         pthread_kill (main_thread, signo);                              \
 225         return;                                                         \
 226       }                                                                 \
 227    } while (0)
 228
 229 #else /* not HAVE_GTK_AND_PTHREAD */
 230 #define SIGNAL_THREAD_CHECK(signo)
 231 #endif /* not HAVE_GTK_AND_PTHREAD */
 232 /* arch-tag: 4580e86a-340d-4574-9e11-a742b6e1a152
 233    (do not change this comment) */